Multiple UV for unwrapped object
You have two materials for one object: StriaStripe and StriaPlum. StriaStripe is on top and was put on the object first, and therefor the object is shown with that material.
If you delete StriaStripe in the Material Properties tab, the object will only have StriaPlum as a material, and then you can see it on your object.
But maybe you don't want to delete it.
In that case you have to select StriaPlum in the Material Properties (click it and it will have a gray bar over it). Then go into Edit Mode with Tab  and press A  to select all the faces of your object. Then click Assign (under the material list in the Material Properties tab), and the faces will get the selected material. Now the object is shown with the other material.
So with the Assign button you can give different materials to different faces, and one object can also have a material on part of the faces, and another material on other faces.